Hello!
I wanted to ask you about an existential doubt that I have had for a long time:
Should ICA be used to clean artifacts if I am going to perform connectivity analysis?
I'm sure in several posts or maybe Brainstorm tutorials I've read that this introduces a common factor and can inflate the connectivity results.
However I am now unable to find those texts and need some backup. I already found an article that indeed advises not to use ICA or PCA in connectivity analysis.
ICA is robust in identifying some sources of EEG artifacts, and it is recommended in most cases. However, a portion of the brain signal permanently gets removed when you remove the ICs.
So, it all depends on the quality of your data; I may recommend first visually checking your data and deciding what to do next.